Dobby for weaving



Feb, 2, 193? R. ROSSMANN 2,069,330

DOBBY FOR WEAVING Filed May 27, 1955 s Sheets-Sheet 1 I INVENTDFQ ,A TgRNEY.

Feb. 2, 1937. R. RO SSMANN v DOBBY FOR WEAYING Filed May 27,1933 3 Sheets-Sheet 2 INN , INVEIJTDF WM U B,

ATFU K Feb. 2, 1937. R. ROSSMANN 7 2,069,330

DOBBY FOR WEAVING- Filed May 27, 1955 3 Sheets-Sheet s Patented Feb. 2, 1931.v

PATENT, OFFICE BOBBY. FOR WEAVING Rudolf Rossmann, Gauting, near Munich, Germany, assignor to Tei Zurich, Switzerland ag Textil Finanz A.-G.,

Applicatiliilil May 2'1, 1933, Serial No. 673,224

Germany 4 CIaima' (cries-c6) This invention relates to dobbies for weaving and is particularly, though not exclusively, applicable to those employing gripping or nipper shuttles.

For the purpose of forming the necessary sheds to produce a desired pattern in'the manufactured fabric a loom has been furnished with a number of shafts constituting heald frames each having an upper and a lower bar or stave, th e healds extending between these staves with a warp thread passing through an eye incorporated in each heald. The necessary up and down or shedding movement has then been transmitted to the heald frames through cords, belts or chains from control mechanism laterally arranged on the loom or above the warp. The overall height of a loom of thistype is however such as not only to necessitate undesirably high ceilinged workshops but'the loom itself tends to obstruct the light and thus add to the difiiculties of the operator. Further, it has been necessary to reduce lubrication of the .dobby parts to an undesirably low value since if adequate lubrication is provided the lubricant tends to find its way on the warp and thereby spoil the manufactured fabric. Again, the drive was not transmitted. from the dobby control mechanism to the heald shafts in a rigid manner and, in some cases, not even positively, with the result that undesirable vibrations were produced in themechanism as a whole. The present invention has for its object toovercome these difflculties. v To this end according to the present invention each heald frame is supported on a rigid bearer longitudinally extending over the whole length of the frame and lying below the shed, and shedding movement is imparted to the bearer byactuating rods positively guided to move vertically. It is obvious that with such an arrangement the frames themselves can be made very light whereby the power and space requirements of the mechanism are considerably reduced.

Preferably each heald frame comprises light longitudinal bars or cords between which extend the healds, and rigid vertical members which ex tend transversely between and connect the longitudinal bars at intervals spaced apart and through which the frame is supported by the bearer. Conveniently each bearer is made hollow and is furnished internally with pins which can be engaged with or disengaged from the actuating rods by relative movement of the rods and bearer in a direction transverse to the length June 2, 1932 ofthe actuating rods. Thus, for example, by moving the bearer in the direction of its length the bearer canbe disengaged from the actuating rods, whereupon the heald frame and warp can be lifted off.

Movement may be transmitted to each actuating rod through a swinging link pivotally connected to the actuating rod, means being provided for swinging the links into or out of engagement with oscillating knives. \Altern'atively movement may be directly transmitted to each actuating rod through a bell-crank lever from card-feeler mechanism..

When the actuating rods are operated by knives cooperating with swinging links, two knives are preferably provided one on each side of a swinging link, the knives being oscillated relatively to each other with that end of the link remote from its connection to an actuating rod engaged by intermediate mechanism actuated by card-feeler mechanism. The knives are preferably oscillated about a centre which lies substantially vertically below the beating up point of the weft 'so that the healds more remote from the beating up point will be moved through a greater distance than the healds nearer to the beating up point, whereby the same shed angle will be obtained by each frame.

In the accompanying drawings:

Figure ,1 is a sectional end elevation of a loom embodying one form of the invention,

','Figure 2 illustrates, on an enlarged scale, the mechanism for transmitting movement .to each heald frame,

Figures 3, 4' and 5 show on a still largerscale three diiferent operative positions of one of the swinging links included in Figure 2,

Figure 6 is a perspective, one larger scale than that of Figure 1, of part of a heald frame,

Figure '7 illustrates an alternative construction 40 of. apparatus for transmitting movement to each heald frame, also according to the invention,-

Figures 8 and 9 show th'manner in which the shed is formed in a loom embodying the invention, and

Figures 10 and 11 are diagrammatic illustrations in side elevation and sectional plan respectively of another form of knife which may be employed for imparting movement to the heald I frames. r

In the construction illustrated in Figures 1 to 6 inclusive the frame I of the loom carries on one of its longitudinal sides a, let-ofl beam 2 from which the warp threads pass over a swing beam 4.

The shed 5 is formed as hereinafter described and the weft picked in and beaten up so as to form the fabric 6 which passes over a breast beam I to a take-up beam 8. The shed 5 is formed by a series of heald frames the upper bars of which are indicated at I911, I91), I90 and I9d, the frames being carried by bearers Illa, I01), I and, Illd which serve to guide the frames during their vertical up and down or shedding -movements. Movement is transmitted to the frames through actuating rods Ila, I Ib, lie and lid and swinging links I211, I21), I20 and I2d, the effective ac-- tuation of these links being controlled through actuating mechanism comprising bars I3a, I3b, I3c, I3d, I4a, I41), I40 and M11 as hereinafter described. Movement is imparted to the links I2a, I2b, I20 and I2d by knives I5a and l5b which are oscillated relatively to each other by face cams I6 engaging bell ,orank levers I'Ia and Nb carrying the knives I5a and l5b respectively.

Figure 2 illustrates the manner in which movement is transmitted to each of the heald frames 7 included in Figure 1. The heald frame comprises a series of transverse supports I8 extending between longitudinal bars or cords I9, the frame being furnished at its lower edge with a flat bearer member I0. Each heald 41 is supported at its ends (Figure 6) on the bars I9 and is furnished with an eye 48 for the passage of a warp thread. The bearer member Ill is hollow as shown and each rod II is provided at one end with a hook 49 adapted to engage a pin 50 arranged inside the guide member I 0. Each heald frame can thus be disengagedfrom its actuating rods I I by simply causing relative movement between the frame and the rods I I in a direction transverse to the length of the rods II.

As clearly shown in Figure 2 each link I2 is pivotally connected at its upper end to its associated actuating rod I I and is furnished at its lower end with a tongue or spike freely movable through an aperture in the bar I3. The rods II are positively guided in a cross-bar 2I asshown and each link I2 is provided with two recesses or forks 49' and 50 adapted to cooperate respectively with the knives I5a, l5b, the pivot 22 of which is arranged vertically below the beating up point of the weft. In this way the heald frames more remote from the beating up point, being operated by the ends of the knives I5a, I 5b, are moved through a greater vertical distance than the frames nearer to the beating up point whereby the angle of the shed is maintained from the beating up point to the. frame most remote therefrom and the same shed'angle will be provided for every pick.

Mounted on a pivot 23 is a short lever 24 to the 7 ends of which the bars I3 and I4 are connected, a pivot 25 carrying a similar lever 26 connecting the other ends of the bars I3 and I4. Link I4 may be omitted. Pivotally connected to the two ends respectively of the lever 26 are two latchpieces 21 and 28, the latch-piece 2'! having a downwardly-directed nose 29 whilst the latch-j connected to a rod 39 guided in a bore in the frame member 3| and capable of engaging the latch-piece 23. The nose. 49 of the rod 39 cooperates with any suitable pattern forming mechanism (illustrated by dotted lines 43) for cooperative movement with the needle or feeler 44 guided in the frame member 3| and having eyes 45 engaged by pins 46 formed on the end of the latch pieces 21 and 28. The needle or feeler 44 rises and lowers in accordance with the desired changes in the pattern.

The operation of the apparatus is as follows:-

In' Figure 3 the frame to which the link I2 is connected has been moved into its uppermost position'as shown, for example, by the frame I90 in Figure 1, the knife I5a engaged with the link I2 having moved upwards as shown by the arrow A in Figure 3, whilst the knife l5b has moved downwards as shown by the arrow B. The movement of the frame now begins to take place in the reverse or downward direction and, when the knives I5a and I 5b arrive at the same level (Figure 4) the bar I3 is moved as hereinafter described so as to turn the link I2 in the direction of the arrow C whereby the knife l5b engages the link I2 whilst the knife I5a is simultaneously disengaged therefrom. As the link I2 is turned into the position shown in Figure 5, the knife I5a moves idly upwards as shown by the arrow D whilst the link I2 and therefore the heald frame associated therewith are moved by the knife l5b downwards in the direction E until the heald frame reaches its lowermost position.

As the cam rotates it rocks the lever 36 about the pivot 38 so as to reciprocate the rod 39. The reciprocating movement of the rod 39 simultaneously causes the latch-piece 28 to be raised and lowered so as to raise and lower the needle 44 which cooperates with a card feeler mechanism which controls the extent of the up and down movement of needle 44. This mechanism is not shown because it is not part of the present invention. The parts are now in the positions shown in Figure 2. As the cam 35 continues to rotate in the direction indicated by the arrow the rod 39 and therefore the needle 44 descends and the latch-piece 28 will move downwards until its nose 3!] lies outside the path of the finger 32, the nose 29 simultaneously moving downwards into the path of the finger 32. The cam 35 now moves the bell crank lever 33 in the clockwise direction as viewed in Figure 2 so that the finger 32 engages the nose 29 and moves the bar I3 so as to turn the links I2 from the position indicated in Figure 3, corresponding to the uppermost position of the heald frame, to the position shown in Figure 5 corresponding to the lowermost position of the heald frame, the knives I5a, l5b cooperating with the links I2 as above described.

The bell-crank lever 33 now commences to move back in the counter-clockwise direction and the cam 35 causes the needle 44 to be lifted. 0n the next descent of the needle 44, the nose 29 will again be brought into the path of the finger 32 but will not be engaged thereby so that the heald frame will not be moved sufficiently in the upward direction to form a new shed. If, on the other hand by the card feeler mechanism, not

'shown, the needle 44 is held in lifted position, the

nose 29 will be held out of the path of the finger 32 whilst the nose 30 will lie in such path whereby on the next operative movement of the finger 32 this will engage the nose 30 and move the bar I4 to the right, thereby moving the bar I3 to the left. In this way as the links I2 move upwards they are turned from the position shown in Figure 5 to the position shown in Figure 4 whereupon the knife l5b will become disengaged from and the knife l5a engaged with the links l2. The knives l5a will then carry the links upwards to the position shown in Figure 3 thereby raising the heald Figure- 7 illustrates an alternative construction in which movement is transmitted to the actuating rods H throughbell-crank levers pivoted on the cross-bar 2 I, a slot 5| in one arm of each bellcrank lever freely engaging a pin carried by the corresponding actuating rod ll whilst the other arm-52 of the bell-crank lever is connected to the bar l3. Pivotally connected to one end of the bar I3 is a latch-piece 21 carrying a pivot pin 53 on V which is mounted a pawl 54 furnished at its opposite ends with noses 55, 56. A lever or knife 51 pivoted at 58 on a fixed part-of the loom is provided at its free end with a nose 59 arranged to cooperate with the nose 55 on the pawl 54. A pin 60 carried by the knife 5! engages a cam groove am in a cam 6|, the cam groove being simul taneously engaged by a pin 62 carried by a. knife 64 pivotedqat 63 and furnished at its free end with a. nose 65 arranged to cooperate with the nose 56 on the pawl 54. The pawl'54 carries a pin 66b which engages a slot 66a in a member 61 carrying the needle 44 and vertically movable within a fixed part 68 of the loom upon which.

part the free end of the latch-piece 21 can slide longitudinally.

One arm of a bell-crank lever 10 pivoted on the frame 66 lies adjacent to the lower end of the member 61 whilst the other arm of the bell crank lever 10 bears against aprojection H formed on the knife 64. 'A spring 12 is connected at one end to the knife 64 and at itsother end to a short lever J3 pivoted at 74, the upper end of the lever 13, which is thus held in engagement with the bell-crank lever 16,-carrying a pawl 15 arranged to cooperate with the teeth 42 of the ratchet wheel M. The projection H is thus peratively connected with the pawl 15 through one arm. of the bell-crank lever 16. I The operation of the apparatus shown in Figure 7 is then as follows:

Assuming that the parts are in the positions shown and that the needle 44 isimmediately over an unperforated portion of the card 43, when the cam 6i rotates in the direction of the arrow the knives and 64 will commence to move inwards towards each other. 'I'he bell-crank lever 70 will now turn in the clockwise direction and the needle 44 will descend and will rest on the unperforated' part of the card 43. The total downward movement of the member 61 will not be suflicient to rock the pawl 54 far enough to move its nose 55 out of the path of the nose 59 on the knife 57 or to move the nose 56 into the path of the nose 65 of the knife 64. As the cam 6i continues tofi rotate the knives 51 and 64 will move further towards each other and the nose 59 engaging the nose 55 will move the bar l3 tothe right and thus raise the heald frame to form ashed. When the two knives 51 and 64 are nearest together the pawl 15 will have moved to engage another tooth' of the ratchet wheel 4| and will be ready to effect the next forward movement of the card 43.

,The knives 5'1 and 64 will now commenceto move apart and the projection H will turn the bell-crank lever so as to raise the needle 44 clear of the card 43, the projection H at the same time moving the pawl to turn the ratchet wheel and advance the card by one step. The knives 51 and 64 are now in the position shown in Figure '7 and, if the needle 44 is immediately over a perforation in the card 43, when the needle descends as above described it will enter the. perforation. The member 61 will thus move downwards sufficiently to rock the pawl 54 so as therefore the nose 65 will engage the nose 56 so as to move the bar i3 to the left and thereby low erthe heald frame to thelowermost position shown.

The heald frame can be readily detached from the actuating rods II by moving the frame tothe rightas viewed in Fig, 7, so that the pins 50 move out of the slots 49. Ready access can be thus had to the parts of the looms beneath the heald frame.

Figs. 8 and 9 illustrate the manner in which the shed is formed due to the operation of the heald frames as above described with reference to Figs. 1 to 5, inclusive. The diagrams Figs. 8 and 9 are. shown in connection with a modification of the knife mechanism designated by Fig.

10. The line constituting the edge of the knives i 5 on Fig. 1 as well as 7 9 on Fig. 10 oscillates around a pivot which is vertically below the beating-up point. For this reason, the heald frames 48, of which only the eyes 48 for letting through the warp threads are shown in Figs. 8 and 9, are raised higher the farther they are from the beating-up point so that the shed angle is the same for every pick.

Figs. 10 and 11 illustrate an alternative form of a knife operating mechanism comprising a disc 18 which carries a knife 79' and which is equivalent to the knives designated in Fig. 1 by numerals i5a and I5?) and in Fig. 7 by-numerals 59 and 65. The disc 18 is slidably and revolvably movable in guides 16 and ll of the stationary carriers 86 and 87. A link is revolvably carried by pin 8! on disc '18; the other end of the link 86 is revolvabiy carried by pin 82 which is mounted to the stationary member having a recess 88 to accommodate link 86. As the disc 18 reciprocatingly moves within guides I8 and H, the disc not only slides along the guides but, at the same time rolls therein. The movement is imparted to disc 78 by a rod 57 between the solid and dotted line positions which has a ball-shaped end wobbling in. a corresponding eye in hub 89 of disc 18. Link 80 is so dimensioned and pin 82 so arranged that the rolling movement of disc 78 causes knife 19 to be turned about animaginary center 22' which lies vertically below the beatingup point of the weft threads.

It will be understood that the constructions above described are given by way of example only and that details may be modified.

' A dobby according to the invention has the advantage that the overall height of the loom is small so that the accessibility and visibility of the parts are facilitated whilst, in addition, the loom does not tend to obstruct \the light unduly. Further, the cost of manufacture is reduced and the tendency for lubricant to fall from the dobby on to the fabric is obviated since the dobby is arranged below the warp and between the take-up and let-off beams.

I claim:

1; In a dobby for weaving, a plurality of individual healdframes, a plurality of bearers indi individually movably engaging all of said bell crank levers connected by means of said actuating rods to the same of said bearers, a pawl carried by each of said longitudinal members, a pair of knives adapted to alternately engage said pawl and move the longitudinal member by which said pawl is carried in substantially the direction of its length, an operating mechanism operatively connected to and adapted to oscillatingly move said knives, and a card feeler mechanism operatively connected to and adapted to control the movements of said operating mechanism.

2. In a dobby for weaving, a plurality of individual heald frames, a plurality of bearers indi vidually supporting said individual heald frames, a plurality 'of actuating'rods individually supportingly connected withe'ach of said bearers, bell crank levers having two arms, always one of i said levers being movably connected by one arm with one of said actuating rods, longitudinal members individually movably engaging all of said bell crank levers connected by said actuating rods to the same of said bearers, a pawl carried by each of said longitudinal members, a pair of knives adapted to alternately engage said pawl and move the longitudinal member by which it is carried in substantially the direction of its length, an operating mechanism operatively connected to and adapted to oscillatingly move said knives, and a card feeler mechanism operatively connected to and adapted to control the movements 'of said operating'nrechanism, said card feeler mechanism comprising a needle-carrier having a lateral arm, and a slot in said arm, said pawl carrying a pin adapted to move within said slot and permit reciprocating movement of said pawl and the longitudinal member by which it is carried.

3. In a dobby for weaving having heald frames each comprising flexible longitudinal members, healds extending between said longitudinal members and rigid upright members interspersed between said healds and extending transversely between and connecting and supporting said longitudinal members, a longitudinal bearer for each heald frame located beneath the shed and rigidly connected to and supporting said upright members, said bearer being hollow and having internally located pins, and actuating rods extending into the inside of said bearer and being removably connected with said pins.

4. In a dobby for weaving having heald frames each comprising flexible longitudinal members, healds extending between said longitudinal members and rigid upright members interspersed between said healds and extending transversely between and connecting and supporting said 1on gitudinal members, a longitudinal bearer for each heald frame located beneath the shed and rigidly connected to and supporting said upright members, said bearer being hollow and having internally located pins, and actuating rods extending into the inside of said bearer, said rods having hooks which engage said pins and are adapted to disengage said pins upon movement of said bearer in a direction transverse to the longitudinal extension of said rods.

RUDOLF ROSSMANN. 

